Masquerading as a default local account

Synopsis

Field	Value
Activation Period	14 Days
Training Period	30 Days
Test Period	N/A (single event)
Deduplication Period	1 Day
Required Data	Requires one of the following data sources: Windows Event Collector OR XDR Agent with eXtended Threat Hunting (XTH)
Detection Modules	Identity Analytics
ATT&CK Tactic	Stealth (TA0005), Persistence (TA0003)
ATT&CK Technique	Hide Artifacts: Hidden Users (T1564.002), Valid Accounts: Default Accounts (T1078.001), Masquerading (T1036)
Severity	Low

Description

A user created a new local account with the name of a default local account, such as Guest and DefaultAccount. An attacker may create a user with these known names to evade detection.

Attacker's Goals

An attacker is attempting to evade detection.

Investigative actions

• Check what rights and permissions were granted to the new user.
• Verify the action with the user who created the new account.
• Follow actions and activities of the newly created default account.
• Monitor the addition of the user to different groups.

Variations

Masquerading as a default local account for the first time

Synopsis

Field	Value
ATT&CK Tactic	Stealth (TA0005), Persistence (TA0003)
ATT&CK Technique	Hide Artifacts: Hidden Users (T1564.002), Valid Accounts: Default Accounts (T1078.001), Masquerading (T1036)
Severity	Medium

Description

A user created a new local account with the name of a default local account, such as Guest and DefaultAccount. An attacker may create a user with these known names to evade detection.

Attacker's Goals

An attacker is attempting to evade detection.

Investigative actions

• Check what rights and permissions were granted to the new user.
• Verify the action with the user who created the new account.
• Follow actions and activities of the newly created default account.
• Monitor the addition of the user to different groups.

Potential masquerading as a power user account

Synopsis

Field	Value
ATT&CK Tactic	Stealth (TA0005), Persistence (TA0003)
ATT&CK Technique	Hide Artifacts: Hidden Users (T1564.002), Valid Accounts: Default Accounts (T1078.001), Masquerading (T1036)
Severity	Low

Description

A user created a new local account with the name of a privileged local account. This user does not regularly create accounts. An attacker may create a user with these known names to evade detection.

Attacker's Goals

An attacker is attempting to evade detection.

Investigative actions

• Check what rights and permissions were granted to the new user.
• Verify the action with the user who created the new account.
• Follow actions and activities of the newly created default account.
• Monitor the addition of the user to different groups.

Masquerading as a default Administrator account

Synopsis

Field	Value
ATT&CK Tactic	Stealth (TA0005), Persistence (TA0003)
ATT&CK Technique	Hide Artifacts: Hidden Users (T1564.002), Valid Accounts: Default Accounts (T1078.001), Masquerading (T1036)
Severity	Informational

Description

A user created a new local account with the name of a default local account, such as Guest and DefaultAccount. An attacker may create a user with these known names to evade detection.

Attacker's Goals

An attacker is attempting to evade detection.

Investigative actions

• Check what rights and permissions were granted to the new user.
• Verify the action with the user who created the new account.
• Follow actions and activities of the newly created default account.
• Monitor the addition of the user to different groups.